strlen() length of a string

#include <stdio.h>
#include <string.h>
int main(void){
char str[100]="plus2net"; // input string
int str_length; // integer variable

str_length=strlen(str); // length of the string
printf("Length of the string  = %d ", str_length);  // final output
return 0;
}

Length of the string = 8

strlen(string);

Example Using one input string

#include <stdio.h>
#include <string.h>
int main(void){
char str[100]; // input string
int str_length; // integer variable
	printf("Enter your string  ");
	scanf("%s",str);
	str_length=strlen(str);
	printf(" Length of the input string :  %d", str_length); // printing outputs
return 0;
}

Length of the string without using strlen() function

#include<stdio.h>
 int main()
{
 char str[12]="plus2net";
 int i=0;
 while (str[i] !='\0'){
// print value of i and value of string at that position. // 
   printf("i = %d : %c \n",i,str[i]); // Output 
   i=i+1; // increment of i by 1 
 }
return 0;
}

i = 0 : p
i = 1 : l
i = 2 : u
i = 3 : s 
i = 4 : 2
i = 5 : n
i = 6 : e
i = 7 : t

#include<stdio.h>
 int main()
{
 char str[12]="plus2net";
 int i=0;
 while (str[i] !='\0'){
// print value of i and value of string at that position. //
   printf("i = %d : %c \n",i,str[i]); // Output
   i=i+1; // increment of i by 1
 }
 printf("Length of the string = %d ",i); // Output as length of the string
return 0;
}

Example 1: Finding the Length of a String

This example demonstrates how to find the length of a string using strlen().

#include <stdio.h>
#include <string.h>

int main() {
    char str[] = "plus2net tutorials";
    int len = strlen(str);
    
    printf("The length of the string is: %d\n", len);
    return 0;
}

The length of the string is: 18

Example 2: Calculating the Length of a User-Input String

This example shows how to use strlen() to calculate the length of a string entered by the user.

#include <stdio.h>
#include <string.h>

int main() {
    char str[100];
    
    printf("Enter a string: ");
    fgets(str, sizeof(str), stdin);
    str[strcspn(str, "\n")] = '\0';  // Remove newline character
    
    printf("The length of the entered string is: %ld\n", strlen(str));
    return 0;
}

Enter a string: plus2net
The length of the entered string is: 8

Example 3: Using strlen() in a Loop

This example uses strlen() to iterate over a string and print each character.

#include <stdio.h>
#include <string.h>

int main() {
    char str[] = "C programming";
    int len = strlen(str);
    
    for (int i = 0; i < len; i++) {
        printf("Character at position %d: %c\n", i, str[i]);
    }
    
    return 0;
}

Character at position 0: C
Character at position 1:  
Character at position 2: p
Character at position 3: r
Character at position 4: o
Character at position 5: g
Character at position 6: r
Character at position 7: a
Character at position 8: m
Character at position 9: m
Character at position 10: i
Character at position 11: n
Character at position 12: g